#include<stdio.h>
#include<string.h>
int main()
{
	int n, i;
	char a[100], b[100];
	scanf("%s", a);
	n = strlen(a);
	for (i = 0; i < n; i++)
		b[i] = a[n - i - 1];
	b[n] = '\0';
	if (strcmp(a, b) == 0)
		printf("yes");
	else
		printf("no");
	return 0;

}